Combination magnetic and electric polarity-indicator



COMBINATION MAGN ETIC AND ELECTRIC POLARITY INDICATOR.

APPLICATION FILED AUGJS. l9|9l Y Patented June 22, 1920.

S14/venten atfoznujo CARL W, EISENMANN, 0F NEBRASKA CITKY, NEBRASKA.

`COMBINATION MAGNETIC AND ELECTRIC POLARITY-INDICATOR.

Specification of Letters Patent. Patented June 22, 1920,

Application filed August 16, 1919. Serial No.y 318,00.

y To all lwhom it may concern:

Be it known that I, CARL W. EISENMANN, a citizen of Germany, residing atNebraska City, in the county of Ctoe and State of Nebraska, haveinvented certain new and useful Improvements in Combination Magnetic andElectric Polarity-Indicators; and I do hereby declare the following tobe a full, clear, and exact description of the invention, such as willenable others skilled in the art to which it appertains to make and usethe same, reference being had to the accompanying drawings, and to theletters and figures of reference marked thereon, which form a part ofthis specification.

This invention relates to new and useful improvements in combinationmagnetic and electric polarity indicators, and consists essentially inthe provision .of a modified compass, with a plurality of indicatingneedles, one of which is non-magnetic and so directed relative to themagnetic needle as to indicate directly the direction of the flow of anelectric current.

My invention consists of a simple and efficient device of this nature,having various details of construction, combination andarrangement ofparts which will be hereinafter fully described, shown in theaccompanying drawings and then specifically defined in the appendedclaim.l

My invention isk illustrated in the accompanying drawings which, withthe letters of reference marked thereon, form a part of thisapplication, and in which:

Figure l is a plan View of my polarity indicator.

Fig. 2 is a cross sectional View through thek same, and y v Fig. 3 is adetail view. Reference now being had to the details of the drawings bynumerals:

l designates a cylindrical casing havin a glass face 1 at each end, saidcylindrica caslng having two spacmg rings 6 therein,

, Said dial is centrally apertured to receive the stafl'1 or pin 3', andupon said staffare mounted two needles, designated respectively bynumerals 3 and 9, at right angles to each other and spaced apartupon'either side of said dial. The ends of said pin have bearings insockets formed in the inner sides of the glass faces.

Cn the side of the dial facing the mag'- netic needle are printed thewords Magnetic direction, and upon the other side of the dial andfacing' the non-magnetic needle appear the words Current direction.7`These needles have definite and fixed relative directions, so that whenviewed from the end of the staffl adjacent the nonmagnetic needle, themagnetic needle will point north and the other west. y

By this arrangement, the needles will have definite fixed directionsaccording to the law of relation between the direction of a current in-the wire and the magnetic field surrounding the wire. For instance,when the instrument is placed over a wire carrying direct current, thenon-magnetic needle will `point directly in the direction of the fiow ofout directly the direction of an electric cury rent, a novel means isprovided.

What I claim to be new is:

The combination of a magnetic and electric polarity indicator,comprising acasing,

a balanced rotatable element consisting of a magnetic and a non-magneticneedle rigidly n secured to a spindle mounted rotatably iny bearings, anindividualy dial for each needle,

said needles being positioned at right angles -to each other inaparticular fixed direction,

so that they respectivelyy indicate the direction of a magnetic fieldand ofan electric current. n

c In testimony whereof I hereunto affix my signature.

CARL W.v EISENMANN.

